Ice maker



Aug. 18, 1953 J. FLETCHER EI'AL ICE MAKER Filed Jan. 19, 1950 PatentedAug. 18, 1953 UNITED STATES ATENT OFFICE ICE MAKER Delaware ApplicationJanuary 19, 1950, Serial No. 139,366

5 Claims.

This invention relates to an ice maker for use in restaurants, bars, orthe like and, more partioularly, to an ice maker adapted to be providedwith city water for the formation of ice including means for preventingsubstantial concentration of minerals in the water used for iceformation without substantial loss in refrigeration capacity of thedevice.

In ice makers of the type contemplated herein, to permit full use ofexisting refrigeration capacity, water to be formed into ice is suppliedfrom a tank to the ice forming members and again returned to the tank.It will be appreciated the water returned to the tank is cooled by theice forming members so that when such water is again supplied to the iceforming members it is substantially at freezing temperature. Hence, therefrigeration effect required to form such water into ice is not greatthereby permitting a small refrigeration system to be employed which maybe operated economically.

Unfortunately, in many areas, the amounts of minerals present in thewater supplied for use in the formation of ice are great. Continualreuse of such water, as required for economical It has been proposed toeliminate mineral de-' posits by continuously bleeding water from thesupply tank while continuously supplying fresh water to the tank; suchpractice, of course, prevents undue concentration of minerals in thewater being used, since the water in the tank is diluted, thuspreventing too high a concentration of minerals therein. Such practiceis highly unsatisfactory in actual operation for it greatly reduces therefrigeration capacity of the device. It reduces the refrigerationcapacity of the device since the fresh water supplied to the tank may beat a temperature of approximately 60 F. for example; thus water in thetank is at an approximate temperature of 60 F. so that when it issupplied to the ice forming equipment it is necessary to reduce thetemperature of such water to 32 F. to permit the formation of ice. Sinceit is necessary for economical operation that water supplied to the iceform ng m r be at a temperature as close to freezing temperatureaspossible, it will be appreciated this proposal is not satisfactorysince it reduces capacity of the equipment, perhaps as much as 25% oreven greater depending upon the amounts of minerals in the water and theconsequent dilution required.

The chief object of the present invention is to provide an ice makerequipped with means for preventing substantial concentration of mineralsin water used for ice formation, without substantial loss ofrefrigeration capacity. Likewise, in vicinities in which a substantialamount of corrosive elements such as acids are present in the wateremployed for ice making purposes which may not freeze into ice, thepresent invention is of value since it prevents substantialconcentration of such elements in the water used for ice manufacture bydilution thereof.

An object of the present invention is to provide an ice maker equippedwith economical means for preventing formation of mineral deposits inthe tank without substantial loss of refrigeration capacity.

A further object is to provide an ice maker in which fresh water issupplied to the machine without substantial loss of refrigerationeffect. Other objects of our invention will be readily perceived fromthe following description.

This invention relates to an ice maker including an ice forming member,means for refrigerating the ice forming member, means for heating theice forming member to harvest formed ice, a water tank, means tocirculate water from the tank to said member, cooled water unused in theformation of ice returning to the tank, and means for preventingsubstantial concentration of minerals in the water without substantialloss of refrigeration capacity, said means including an element forsupplying fresh Water to the tank, means for bleeding water from thetank, and means for placing the stream of fresh water being supplied tothe'tank in heat exchange relation with the stream of water beingremoved from the tank.

The attached drawing is a diagrammatic view of an ice maker embodyingthe present invention.

Referring to the drawing, there is shown an ice maker including aplurality of tubes 2 in which ice is formed. An evaporator 3 of arefrigeration system is disposed about the exterior wall of the tubes inorder to cool spaced portions of the tubes to form separate pieces ofice. Evaporator 3 isa portion of a refrigeration system which includes acompressor 4 connected by a line 5 to a condenser 6, condenser 6 beingconnected to evaporator 3 by line 1 in which an expansion means 8 suchas a capillary tube or expansion valve is placed to regulate flow ofrefrigerant to evaporator 3. A line 9 connects evaporator 3 withcompressor .4; preferably, an accumulator I i) is placed in line 9to-prevent liquid refrigerant passing to the compressor 4. Condenser 6may be water-cooled by the supply of city water through line H in heatexchange relation with refrigerant therein although, if desired,pendenser may be air-cooled.

To harvest ice formed in tubes g, ;a line I g rnay be providedconnecting line 5 with line i to permit hot gas from the compressor tobe circulated through evaporator 3. A solenoid valve l3 may be providedin line l2 and actuated auto.- matically in response to an indicationthat the formation of ice in tubes 2 is complete to harvest formed ice,When the harvesting operation is complete, valve l3 may be againactuated to resume operation of the refrigerating system in the usualmanner.

A water supply tank 38, preferably, is below tubes '2 or is connected tosuch tubes in any suitable manner in order that water passing throughthe tubes is returned to tank I8. As shown pump P withdraws water fromtank l8 and supplies sufiicient water through line 2 to supply members2! placed above tubes 2; preferably targets 22 are placed within tubes 2in order that the sprays of water are directed to the interior wall ofeach tube, A screen or grating 23 is placed beneath tubes 2 to permitformed ice to be directed to a bunker (not shown) while permitting waterpassing through the tube to be returned to tank [8.

In the present invention, fresh water is supplied to tank it while wateris continuously drained from tank It to prevent concentration ofminerals in the water the tank. fresh water supplied to tank 58 be at atemperature of approximately 60 as is customary when city water isemployed in the formation of ice. The water leaving 8 to waste may be ata temperature of about 33 F. since it been cooled greatly by passingthrough tubes 2. As shown, the fresh water line 2,4 is connected tocondenser water line H. Line 26 is connected to a heat exchanger, 25hereinafterdescribed while line 25 connects heat exchanger .25 with tankis. Th bleed line 2] is connected to an inlet-8 adjacent one end of heatexchanger 25, and outlet 29 is provided in heat exchange-r25 to permitthe Water containing ninerals to flow through line 38 to a suitabledrain. To permit the water bleeding from the tank to be vented, abypassline 36 is provided.

Heat exchanger 25 contains a coil -31 connected to lines 25 and 25 topermit fresh water flowing to tank ill to pass therethrough. To permitWater to be easily removed from ;'heat exchanger 25 when it is desiredto clean the exchanger, a drain 32 may be provided therein.

Considering the operation of the devicatherefrigeration equipment coolsthe walls of tubes 2 while simultaneously pump P circulates water fromtank 28 through tubes 2. Water draining from tubes 2 returns to tank 18.Within a short periodof time it will be appreciatedthetemperature of thewater in tank 18 is at approximately freezing temperature. When asatisfactory quantity of ice is formed in tubes 2, solenoid valve 53 maybe actuated to supply hot gas to evaporator 3 thereby thawing the-icefrom-the in- 4 terior wall of the tubes. The formed ice drops from thetubes onto grating 23 and is forwarded by forces of gravity to asuitable bunker.

While the refrigerating and harvesting steps are being conducted, freshwater is supplied through line 2 5 to heat exchanger 25 and from heatexchanger 25 through line 26 to tank i8. At the same time, water fromtank E8 is continuously removed through line 2? to heat exchanger 25 inheat exchange relation with the fresh water passing through coil 3! andthen flows to a drain. Fresh water entering heat exchanger 25 may be ata temperature of about 60. Water flowing from tank is is at atemperature of about 33 F. The fresh water passes through line 25 totank 18 and is lowered in temperature to about 48 F. while the waterfrom tank it going to waste is raisedin temperature to about 57 F. Itwill be understood the temperature of the fresh water so obtaineddepends upon the percentage of waste water compared to the percentage ofwater frozen; with waste water approximately equal to the amount ofwater in the formed ice the temperature is about 48 F. By this means therefrigeration effect is saved, permitting smaller refrigerationequipment to be employed and reducing the cost of operation whilepreventing formation of mineral deposits in the tank.

The present invention provides an ice maker including means forpreventing concentration of minerals in the water used for ice formationwithout substantial loss of refrigeration capacity. The means soprovided do not materially increase the cost of operation of the deviceand do not materially affect initial cost.

While we have described a preferred embodiment of our invention it willbe understood our invention is not limited thereto since it may beotherwise embodied within the scope of the following claims.

We claim:

1. In an ice maker, the combination of a pluirality of tubes in whichice is formed, means for refrigerating the tubes including awater-cooled condenser, means for heating the tubes to harvest formedice, a water tank, means to circulate water from the tank through thetubes while the tubes are being refrigerated, cooled water unused in theformation of ice returning to the tubes, and means for preventingsubstantial concentration of minerals in the cooled water Withoutsubstantial loss of refrigeration capacity, said means including acontrol for maintaining a desired level of water in the tank, a linethrough which cooling water is supplied to the condenser, a lineconnected to the condenser water line for continuously supplying freshwater to the tank, a third line connected to a drain for bleedin Waterfrom the tank, a shell member in the third line containing an inletadjacent one end and an to prevent concentration of minerals in thesupply water without reducing the refrigeration capacity of the icemaker, the steps which consist in forming ice while cooling water fromwhich the ice is formed, returning the cooled water to a water-reservoir, supplying a stream of water from the reservoir for iceformation, bleeding a second separate stream of water from the reservoirto prevent concentration of minerals in the water supplied for iceformation, supplying a stream of fresh water to the reservoir, passingthe second stream and the stream of fresh water in heat exchangerelation to prevent substantial loss of refrigeration capacity by theremoval of cooled Water from the reservoir, harvesting the formed icewhile discontinuing ice formation, then discontinuing the harvestingoperation, and repeating the steps automatically until a desired amountof ice is formed.

3. In a method of operation of an ice maker the steps which consist inrefrigerating an ice making element, supplying an excess of water from areservoir to the element for the formation of ice thereby cooling waterunused in ice formation, returning the cooled water to the reservoir,again supplying an excess of water from the reservoir to the ice makingelement, bleeding water from the reservoir to prevent concentration ofminerals in the water supplied for ice formation, replenishing thereservoir with fresh water, passing the streams of fresh water and wastewater in heat exchange relation to prevent substantial loss ofrefrigeration capacity by the removal of cooled water from thereservoir, discontinuing supply of water to the ice making element andrefrigeration of the ice making element, heating the ice making elementto harvest formed ice, then after harvesting discontinuing heating ofthe ice forming element and again supplying water to the ice makingelement and refrigerating the same.

4. In an ice maker, the combination of an ice forming element, means forrefrigerating the element including a water cooled condenser, means forharvesting formed ice, a water tank, means for circulating water fromthe tank to the ice forming element while the element is beingrefrigerated, cooled water unused in the formation f ice returning tothe tank, and means for preventing substantial concentration of mineralsin the cooled Water without substantial loss of refrigeration capacity,said means including a control for maintaining a desired level of waterin the tank, a line connected to the tank for supplying a stream offresh water directly thereto, flow of fresh water through said linebeing regulated by said control, a second line connected to a drain insaid tank for bleeding a stream of Water from the tank, and means insaid lines for placing said streams in heat exchange relation.

5. An ice maker according to claim l in which said heat exchange meanscomprise a shell, a coil in said shell, and inlets and outlets to saidshell and coil for the fresh water and the waste water arranged to passthe stream of fresh Water in counterflow heat exchange relation with thestream of water removed from the tank.

JAMES L. FLETCHER. SAMUEL C. OSBORNE.

References Cited in the file of this patent UNITED STATES PATENTS Number

